The Family Investigation of Nephropathy and Diabetes (FIND) is designed to identify genes responsible for diabetic nephropathy and their linkage relationships, if any, to nephropathy. The goal of this study of diabetic retinopathy in this population is to evaluate whether there is a genetic link between diabetic nephropathy and diabetic retinopathy. Are there genetic factors that predispose to both diabetic nephropathy and retinopathy? Are there genetic factors that predispose uniquely to either retinopathy or nephropathy respectively? A secondary goal is to perform a genetic linkage study of more severe diabetic retinopathy. The NIDDK-sponsored FIND study will recruit probands with diabetic nephropathy and their family members. The majority of the probands will be affected with diabetic retinopathy of various degrees of severity. FIND is a multi-center consortium, comprising eight (8) Participating Investigator Centers (PICs) and a Genetic Analysis and Data Coordinating Center (GADCC), established to study the genetics of Diabetic Nephropathy. Seven (7) of the PICs, a central fundus photograph reading center, and the GADCC are participating in the retinopathy study. The charge of the consortium is to acquire sets of families with well-characterized diabetic nephropathy, establish a secure master FIND database, and perform a genome scan to identify chromosomal regions linked with diabetic nephropathy. Analytic methods will include a) affected sibling pair (ASP), discordant sibling pair (DSP), affected relative pair (ARP), and discordant relative pair (DRP) linkage analyses. Probands and family members who are diabetic will undergo an eye examination and fundus photography. The affected probaland, the affected sibling pair/discordant sibling pair and affected relative pair/discordant relative pair will participate in the retinopathy study. This study is still enrolling patients and the analysis phase will begin in the near future. Recruitment will end in early 2006.